Generally, compressors are divided into compressors for compressing compressible fluids such as air, gas, refrigerant, etc., and hydraulic compressors for compressing and feeding incompressible fluids such as oil, water, etc., according to media to be compressed. Further, the compressors are variously divided into piston compressors, screw compressors, centrifugal compressors, scroll compressors, and so on, according to compression methods.
For example, the piston compressor conventionally compresses air, etc. by a reciprocating movement of a piston so as to generate a rotary force delivered to an engine or a motor, and feeds the compressed air to a power transmission system such as a crankshaft or a connecting rod. Herein, since much rotary force delivered to the power transmission system to change the reciprocating movement to a rectilinear motion is consumed, the piston compressor reduces a compression efficiency, and increases the generation of vibration and noise.
The recently developed scroll compressor comprises a pair of scrolls, i.e., a rotary scroll and a fixed scroll, and a plurality of variable compression chambers. The scroll compressor decreases the dimensions of the compression chambers by the rotation of the rotary scroll within the variable compression chambers, and thus compresses a media introduced into the compression chambers. Compared to the piston compressor, the scroll compressor improves a compression efficiency and reduces the generation of vibration and noise. However, since the rotary scroll has a complicated structure, the scroll compressor is difficult to manufacture.
With reference to FIG. 1, a conventional vane compressor comprises a cylinder chamber 70, a rotor 71, and vane members 72A-R. The cylinder chamber 70 compresses an introduced medium and extrudes the compressed medium in a hermetically sealed state. The rotor 71 is rotated about its eccentric axis so that an outer circumference of the rotor 71 partially contacts an inner circumference of the cylinder chamber 70. A plurality of the vane members 72A-R are radially arranged along the eccentric axis of the rotor 71, and contact the inner circumference of the cylinder chamber 70, thereby extruding the compressed medium.
A plurality of vane slots 73A-R for accommodating the corresponding vane members 72A-R are radially formed on the circumference of the rotor 71. A spring (not shown) for compressing and extending each of the vane members 72A-R is installed within the vane slots 73A-R.
Hereinafter, an operation of the aforementioned conventional vane compressor will be described in detail. When the rotor 71 is rotated, the vane members 72A-R are also rotated within the cylinder chamber 70 by the rotation of the rotor 71. Then, outer ends of the respective vane members 72A-R contact the outer circumference of the cylinder chamber 70 and are rotatably slid along the outer circumference of the cylinder chamber 70. At this time, the outer ends of the respective vane members 72A-R are elastically compressed and stretched by the springs installed between the vane members 72A-R and the vane slot 73A-R according to their contact positions with the outer circumference of the cylinder chamber 70.
For example, in case one of the vane members 72A-R has the maximum length from its outer end to its contact point with the inner circumference of the cylinder chamber 70, this member of the vane members 72A-R is maximally protruded from the corresponding slot of the vane slots 73A-R by the elastically stretched force of the spring installed in the corresponding slot of the vane slots 73A-R and firmly contacts the inner circumference of the cylinder chamber 70. On the other hand, in case one of the vane members 72A-R has the minimum length from its outer end to its contact point with the inner circumference of the cylinder chamber 70, this member of the vane members 72A-R is maximally inserted into the corresponding slot of the vane slots 73A-R by the elastically compressed force of the spring installed in the corresponding slot of the vane slots 73A-R and firmly contacts the inner circumference of the cylinder chamber 70. Therefore, the vane members 72A-R are compressed and stretched according to their positions within the cylinder chamber 70. As a result, the vane members 72A-R are pushed toward the inner circumference of the cylinder chamber 70 by the high-speed rotary force of the eccentrically rotated rotor 71 and the restoring force of the springs of the vane members 72A-R compressed and stretched according to their contact positions within the cylinder chamber 70, thereby maintaining the sealed state of the cylinder chamber 70 required to suck and compress a fluid.
As described above, when a medium is introduced into the cylinder chamber via a fluid suction section 74A or 74B, the rotor 71 eccentrically rotates. Then, the medium is compressed by sealed spaces formed between the plural vane members 72A-R and the inner circumference of the cylinder chamber 70 and extruded to the outside via a fluid exhaustion section 74D.
However, since the outer ends of the vane members 72A-R of the aforementioned conventional compressor are comparatively flat, there is a gap A between the outer end of the vane member and the inner circumference of the cylinder chamber 70. The highly compressed fluid pushes the vane members 72A-R in the direction to the eccentric axis of the rotor 71 via the gap A within the cylinder chamber 70. Therefore, the hermetically sealed state between the vane members 72A-R and the inner circumference of the cylinder chamber 70 maintained by the high-speed rotary force of the eccentrically rotated rotor 71 and the restoring force of the springs of the vane members 72A-R according to their contact positions with the inner circumference of the cylinder chamber is broken, and thus the compressed fluid is leaked via the gaps A of the vane members 72A-R.
Moreover, since the aforementioned compressor comprises a plurality of the vane members 72A-R installed along the circumference of the rotor 71 so as to maintain the hermetically sealed state of the cylinder chamber 70, the dimensions of spaces for compressing the fluid within the cylinder chamber 70 is reduced by the dimensions occupied by the vane members 72A-R, and thus the compression efficiency of the compressor is deteriorated.